Fats play a variety of essential processes in humans including but not limited to: adipokine secretion, cell membrane formation, protection/insulation of organs, and storing and releasing energy.
Many health and fitness enthusiasts seem to have an irrational fear of saturated fats and seek to greatly limit their intake of them. This generally manifests itself into complete avoidance of foods like full-fat dairy products, egg yolks, butter, fatty meats, coconut, etc. While it is indeed not a good idea to over eat saturated fats, there is still a place for them in everyone’s diet.
What are saturated fatty acids?
Fatty acids are comprised of hydrocarbon chains that may or may not contain double bonds. Saturated fatty acids differ from unsaturated fatty acids in that each carbon in the fatty acid chain is saturated with hydrogen atoms (i.e. no double bonds exist in the hydrocarbon chain).
Why fatty acid chain length matters
Further chemical classification of saturated fatty acids takes into account how many carbons are in the hydrocarbon chain; less than 6 carbons denotes short-chain fatty acids, 6-11 carbons denotes medium-chain fatty acids, more than 11 carbons denotes long-chain fatty acids, and more than 22 carbons denotes very long-chain fatty acids.
One of the reasons certain fat sources like butter stay solid at room temperature is because the melting point of saturated fatty acids increases as the carbon chain lengthens. On the contrary, foods rich in unsaturated fatty acids, like olive oil, are usually liquid at room temperature (e.g. melting point is lower).
In the case of short and medium-chain fatty acids, digestion entails passive absorption into the blood by way of the intestinal capillaries. This differs from long-chain fatty acid metabolism, which are absorbed by villi in the walls of the intestine and subject to further modification. For this reason, SCTs/MCTs serve as excellent energy sources due to their simple metabolism.
SCTs are primarily found in the milk fats from cows, goats, and sheep. Coconut is a rich source of MCTs, but if you’re looking for an alternative you can buy MCT oils from various sources as well.
How trans fatty acids are made
Despite being unsaturated fatty acids, it’s worthwhile to quickly cover the topic of trans fatty acids. Trans fatty acids are found in some food products naturally, albeit in minute amounts. Most foods with a significant amount of trans fatty acids are the result of a process known as hydrogenation. Essentially, hydrogenation is the chemical modification of a fatty acid so that a “trans” double bond is created in the hydrocarbon chain; these trans double bonds cause the fatty acid tail to maintain a linear configuration and behave differently then normal unsaturated fats, which are primarily composed of “cis” double bonds.
Research continues to grow on the deleterious effects of too much trans fatty acid intake in the human body. It is generally advised to greatly limit, if not completely omit, your intake of foods high in trans fatty acids. Risks of significant trans fat intake include: lower HDL, elevated LDL and other cardiovascular maladies.
So how much saturated fat should we eat?
Saturated fats appear to be correlated with sex hormone (androgen) production in males, so it is generally not a good idea to greatly limit your saturated fat intake. On the flipside, chronic superfluous saturated fat intake may induce insulin resistance and other metabolic maladies, so we don’t want too much either.
Given that the calorie needs and goals of individuals vary from person to person there is no preset, unanimous amount of saturated fat that everyone should eat. However, as a general starting point, active individuals should aim to get roughly 25% of their total fat intake in the form of saturated fats. As an example, if you’re ingesting 80g of fat per day, roughly 20g or so of that should be saturated fats.
Exceptions to this rule are people who follow strict keto/low-carb diets may have to since their fat intake tends to be exorbitantly high. Contrarily, if someone is on a low fat diet (<30-40g of fat), they may need to eat more like 30-40% of those in the form of saturated fats just to support nominal hormone production, among other things.
As with most diet recommendations, be prepared to do some trial and error with your plan. There is no lone cookie-cutter optimal diet plan out there. Be willing to try different approaches and find what works for you.
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